ARM Template resources tags with condition - tags

Question

I've created my ARM templates to publish azure resources on my dev environment.
Now I need to add a condition in template.json for resource tags, that it will create tags only if subscription().displayName is 'Dev'.
Other than 'Dev', it should not create any tags from that template.json under resources.
"resources": [
{
"type": "Microsoft.Web/connections",
"apiVersion": "2016-06-01",
"name": "[parameters('connections_office365_name')]",
"location": "[resourceGroup().location]",
"properties": {
"displayName": "manish.jain#gmail.com",
"customParameterValues": {},
"api": {
"id": "[concat('/subscriptions/',subscription().subscriptionId,'/providers/Microsoft.Web/locations/',resourceGroup().location,'/managedApis/office365')]"
}
},
"tags": {
"Creator": "Manish Jain",
"Environment": "Dev",
"Date": "08/31/2019"
}
}

Answer 1

The following ARM template demonstrates how to make the whole tags dictionary conditional:
{
"$schema": "http://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"location": {
"type": "string"
},
"storageAccountName": {
"type": "string"
},
"accountType": {
"type": "string"
},
"kind": {
"type": "string"
},
"accessTier": {
"type": "string"
},
"supportsHttpsTrafficOnly": {
"type": "bool"
},
"createTag": {
"type": "bool"
}
},
"variables": {},
"resources": [
{
"name": "[parameters('storageAccountName')]",
"type": "Microsoft.Storage/storageAccounts",
"apiVersion": "2019-06-01",
"location": "[parameters('location')]",
"properties": {
"accessTier": "[parameters('accessTier')]",
"supportsHttpsTrafficOnly": "[parameters('supportsHttpsTrafficOnly')]"
},
"dependsOn": [],
"sku": {
"name": "[parameters('accountType')]"
},
"kind": "[parameters('kind')]",
"tags": "[if(parameters('createTag'),json('{\"tag1\": \"value1\",\"tag2\":\"value2\"}'), json('{}'))]"
}
],
"outputs": {}
}
To apply this to your particular scenario, instead of [if(parameters('createTag')... it would be [if(equals(subscription().displayName,'Dev')...

Answer 2

The conditional tags using an if block works; however, is it the best practice?
If you are creating tags conditionally based on environment, why not create the tag values as parameters and pass them into your ARM template.
That would avoid the whole conditional piece and instead the specific tag values defined in the parameters template will be inserted into the ARM template.
The downside to this approach would be that the tag values would be required for each environment as opposed to just your lower environment. However; your consistency would improve as each environment can all have the same tags and just different values.